-
july • august 2014 winc 5
Ibet you would need to go to a rather remote placeon the planet
to find someone who is not familiarwith this song. And it would be
harder to find any -one in the South who has not had an experience
with theplant itself. For the lucky ones, perhaps the experienceis
only through a family member or classmate. In thatcase often a good
laugh, right? If there were some wayto tally up all the negative
encounters with hornets,bees, poisonous snakes, sharks,
disease-bearing ticks,skunks, jellyfish stings, lighting and
perhaps even fireants, I suspect rashes from poison ivy would
outscoretheir combined suffrage.
Poison ivy is but one of over 700 North Americanplants known to
be toxic to people or livestock. Thelist includes algae, fungi,
lichens, ferns, horsetails, certainpines and various flowering
plants. The majority of theseare poisonous only if eaten, but
poison ivy and its rel a -tives are unusual in that their poison
can be trans mittedby simple contact with the plant. Did you ever
wonderabout all the products that boast “made of 100 percentnatural
ingredients?” Well, perhaps you should, becausetoxic plants are
packed with only natural substances.So here is a little hint, don’t
try to eat poison ivy, the all-natural plant, as it can get you
that way too.
Poison ivy, a ubiquitous species, grows throughoutmost parts of
the eastern and central United States andsouthern Canada. It is
found throughout the South.People become confused because this
plant does notalways take on its ivy-like growth habit. Poison ivy
cangrow into an ivy-like vine, a woody shrub or simply aslittle
woody stems poking upward from the forest floor.
The syndromes caused by poison ivy have beenknown since the days
of Captain John Smith and theyhave been described in various
American Indian cultures.This plant was one of the earliest
formally named NorthAmerican species when Jacob Cornutus described
it inhis “Plantarum Canadensis” in 1635. Since then the tax -onomic
name has been revised several times, and thecurrent name for the
genus does not even have a Latinequivalent and dates back to one
used by ancient Greeksfor Old World plants with similar toxic
traits.
“Leaves of three, let it be.” This seeminglyinnocuous vine has
been the scourge ofcountless outdoor enthusiasts.
Poison Iv-y-y-y-yMeasles make you bumpy
And mumps’ll make you lumpy
And chicken pox’ll make you jump and twitch
A common cold’ll fool ya º
And whooping cough can cool ya
But poison ivy, Lord’ll make you itch!!
©Jerry Leiber & Mike Stoller, 1959
-
july • august 2014 winc 7
exposure is from contact with the toxinsthem selves, and
generally not contact withthe rash that develops later.
• Inhalation of airborne urushiol thatcan occur when a lawnmower
or trimmer isused to cut down poison ivy vines or shrubs.Inhalation
of urushiol causes the rash toappear on the lining of the lungs
causingsevere pain and respiratory dis tress.
• Inhalation of smoke from burningpoison ivy.
• Eating poison ivy.• While it is widely believed that one
can
infect other areas of their body from the weep -ing blisters or
that it spreads from scratching,this is not generally believed to
be the case.Nor can people spread the infection from oneperson to
another. Fluids oozing out from theblisters cannot spread the rash
on you or toanother person. The oozing blisters are mostly
just body fluids. But be careful of what youlearn from books. I
know a colleague thatpublished a paper in the prestigious
medicaljournal, The Lancet, on infection to his partneras a result
of sexual transfer. Bet you neverthought of poison ivy rash as a
sexually trans -mitted disease. Good science experimentsneed to be
confirmed by replicate research, butI am unable to find anything in
the medicalliterature about follow-up studies. I suspectresearchers
had trouble recruiting volunteersfor the follow-ups. I may be wrong
but I betsome college students would raise their hands.
Poison ivy most often has groups of threeleaves, but it may have
five or seven. Theleaves may be notched or have smoothedges. Poison
ivy berries become glossywhen ripe. A big hairy vine growing up
atree is a very visible warning sign.
I was never one to dwell on the symbolic.I recall a final exam
in American literaturewhere the entire grade rested on answeringthe
question “Explain the religious symbolismin Steinbeck’s “Grapes of
Wrath.” While thiswas intended to be a multi-level question
myanswer was short and simple “You guys couldfind religious
symbolism in a Batman comicbook!” I aced the test. I was in high
schoolwhen The Coasters’ “Poison Ivy” hit thecharts, and because of
my disregard for thesymbolic even back then, I did not have
anyreason to believe that the lyrics were aboutanything but the
rashes produced by theplant. Now I find out that many suspect
thesong is not about a plant at all, but rather a young lady with a
social disease. The ironyof my colleague’s published findings
can’tbe ignored.
And speaking of Batman comic books andfemales that make you
itch, the idea of poisonivy being an evil female surfaces again.
PoisonIvy, one of the more toxic of the Gotham Cityvillains, is
portrayed as an eco-terrorist, pro -tecting the environment in ways
that requireBatman’s intervention. Wearing her sexy ivy
She comes on like a rose but everybody knows She’ll get you in
Dutch
You can look but you better not touch
6 july • august 2014 winc
So here are the ABCs of concerned people’smost frequent
questions.
How does the poison work? The plant produces an organic oil
calledurush iol which causes an allergic skin rashon contact. This
is known medically asurushiol-induced contact dermatitis. Theskin
rash causes intense itching and leads tothe formation of blisters.
Open blisters leadto sores and these sores can become infected.The
urushiol produced by poison ivy is verypotent and can remain active
for several yearsafter the plant is dead.
The toxin is a colorless to milky substancethat is contained in
the resin canals of theplant. It is found throughout the
plant—roots, stems, leaves, flowers and fruits—andis only absent
from the plant’s pollen. Thechemistry of the toxic substance is a
3-n-pentadccylcatechol, and the sensitizingcompounds are alkylated
dihydroxy phends.
See, you should have paid attention in organicchemistry class.
There are actually four dif -ferent poisons in the chemical chain.
Thecombination of the toxin with skin proteinsstarts the
reaction.
The words poisonous and toxic are usedinterchangeably even in
the circular defini -tions of dictionaries. Biologically plants
andanimals that contain poison are poisonous(rattlesnakes, spiders,
gila monsters, poisondart frogs, jellyfish, and mushrooms
forinstance). The poison can be injected oringest ed. Toxic plants
and animals are onesthat secrete chemicals that then react
withchemicals in our bodies (toxic plants, chig -gers, licking
toads and inhaling chemicalfumes). But there are all sorts gray
areas, andsome things could be toxic to your skin andpoisonous if
you ate them. And then there isnuclear poisoning and all the
various deadlytransgressions they do in James Bond movies.So I
think most people have just given up and
use whichever term gets the best attention.But if you come in
contact with toxic ivy ortoxic oak there is probably no immediate
needto call the Poison Control Center ’s hot line.
OK, it can be bad stuff; so how can I avoid it? You can stay
indoors or perhaps move toGreenland. Otherwise it’s hard to stay
awayfrom poison ivy, as it grows pretty mucheverywhere. Your best
bet is to learn to iden -ti fy the plant. The plant’s appearance
can bedeceptive because of its various growth forms.
The leaflets of poison ivy are usuallyarranged in groups of
three, but they mayalso appear in fives or sevens. In each
cluster,the middle leaflet grows on a stalk that ismuch longer than
those on the sides. Theleaflets in the compound leaf are
usuallyfairly equal in size, but the individual leafletscan vary
greatly in size—from one-half to2 inches long. Their edges may be
slightly
notched or smooth. Theyare shiny when young andturn a brilliant
red in fall. Theflowers of poison ivy are yel -lowish to
greenish-white, aboutone-quarter inch in diameterand grow in
clusters on a slen -der stem. Small, berry-like,whitish or greenish
fruit, about
one-sixth of an inch across, appears after theflowers have faded
and are glossy when ripe.
What about similar appearing non-poisonous plants?OK, so you
have no desire to become aback yard botanist. Just avoid anything
youthink might be poison ivy. Recall all the funevery one had at
summer camp when poisonivy was an endless source of pranks
andjokes, mostly at others’ expense. But youcan learn to
distinguish poison ivy fromother native plants by means other than
atrial-and-error approach.
There are a number of woody vines andshrubs that have compound
leaves that aresuperficially similar to poison ivy. Many ofthem
grow in the same habitats, often sideby side with poison ivy. The
trifoliate (threeleaflets) leaves of poison ivy are arranged inan
alternate fashion, and this combinationalone eliminates many of the
plants that one
might confuse with poison ivy. Additionally,other plants have a
variety of flowers, fruitsand seedpods that are not anything like
thesmall greenish white flowers or the whiteberries—actually
drupes—of poison ivy.The simplest thing is to just learn what
poisonivy looks like and then avoid any plant thatyou think even
looks like it.
What other toxic plants do we need to worry about?Other
poisonous plants similar to the poisonivy include poison oak and
poison sumac.For many people, including botanists, thereis some
confusion regarding names of ourtoxic plants. This won’t help one
bit, but youshould know that poison ivy is not an ivy andpoison oak
is not an oak. They, like poisonsumac and other sumacs, are members
ofthe family Anacardiaceae.
In its shrub form, poison ivy is often calledpoison oak. Then
there is a second speciesalso found in the South that is named
poisonoak. It never takes on vine-like growth; it’ssimply a plant
with woody stems that growsin dry sandy habitats where poison ivy
doesnot grow. Many botanists believe that this“poison oak” is
simply a variety of poisonivy and not a true species. True poison
oakis a plant found only on the Pacific Coast ofthe United States
and of Canada. Our poisonoak is found in dry woodlands, thickets
andabandoned fields of the Coastal Plain andlower Piedmont. And
then there is poisonsumac, another plant closely related to
poisonivy. It grows in swamps, bogs and pocosinsin the eastern
North America. It can grow upto 15 feet in height, and like other
sumacshas compound leaves with seven–11 leaflets.
How Does One Get Poison Ivy?The following are the ways by which
poisonivy can infect the body:
• Skin contact with a poison ivy vine orshrub, with secondary
spreading to other skinsurfaces by urushiol on the sufferer ’s
hands.Try to avoid rubbing eyes with your hands.
• Skin contact with items such as clothingor garden tools that
have been exposed tourushiol from poison ivy.
• Skin contact with people or animals thathave been exposed to
poison ivy. Animals areusually immune to poison ivy. Secondary
She’s pretty as a daisy but look out man she’s crazy She’ll
really do you in If you let her under your skin
-
it-alls, who everyone, including the teacherhates. Well we know
from experience thatthey really do exist and it’s an unusual
classthat does not have at least one. I had the goodfortune to have
one in my college botany class,and then another years later in a
class I wasteaching, who each took delight in showingeveryone on
respective field trips that theywere immune and vigorously rubbed
poisonivy leaves on their arms and legs. In the daysthat followed
it was clear that they were mis -taken about their super powers,
and we allacquired a new level of appreciation for theplant. OK, I
probably should have informedmy student of the changing nature of
one’sbody reaction to the plant, but it’s hard toignore a good
teaching moment. You have gotto love nature.
Actually no one gets a reaction on firstexpo sure, but your body
becomes sensitizedto it, and some people require repeated expo
-sures before their skin reacts to the plant’s oils.However, most
if not all people who continueto have no allergic response will
become sensi -tized over time with repeated or concentratedexposure
to urushiol. Studies conducted inthe mid-70s showed that about 40
percent ofpeople exposed to the quantity of urushiol injust a piece
of a leaf one-quarter inch in dia -meter will have a reaction. This
increases toabout 75 percent in stronger doses.
Even minor reactions are annoying andunpleas ant. You can always
just scratch, butit does not do a bit of good, although it
feelsgood while you are doing it. You do have tobe concerned about
the secondary skin infec -tions resulting from your scratching
later.
Some Other Stuff You Might Want to Know To those susceptible to
poison ivy the newsis increasingly bad. As a result of land
clearingand global warming, the plant is increasingin abundance and
toxicity. Poison ivy needssun and it thrives in open situations and
alongthe edges of woodlands. In our yard in Raleigh,the plant was
everywhere when we purchasedthe property in the mid-70s, but as the
forestmatured and the property became more shad -ed it mostly died
out. Today the plant growsentirely near the edges of our woods in
theform of large woody vines. The ivy climbshigh into the pines and
oaks, vines the size
TreatmentWithout treatment thedermatitis will clear up in10 to
21 days. Dependingon the severity, contem -porary treatment
optionsare as follows:
1. Removal of the antigenfrom the skin with alcoholor alkali
soap.
2. Application of cold watercompresses to
alleviateinflammation.
3. Applying commerciallotions to reduce itching.
4. Local or systemic adminis -tration of cortisone drugs.
5. Use of antihistaminicdrugs to reduce itching.
6. Use of antibiotics to mini mize secondarybacterial
infections.
of my arms climb 40 feet and more into ourtrees. Back in the
woods, 20 to 30 feet awayfrom the edges, the ivy totally
disappeared.Global warming is altogether another issue.Warmer
temperatures makes plants moretoxic, as does increased levels of
carbondiox ide. Both have a positive effect on theconcentrations of
urushiol. Years back, thefirst summer I worked in Florida, I had
anextremely bad reaction to poison ivy. At thetime I did not
understand why the same plantthat had I frequently encountered many
timesin Maryland with mild reactions, in Floridacaused severe
swelling and large oozing blis -ters. Studies comparing the
chemical compo -sition of the principal active components ofthe
urushiol in poison ivy leaves from NewYork, Maryland and
Mississippi showed thatthere is considerable geographic variation
inthe plant’s potency.
The plant is not without merit. Poison ivyis a native species
and it does have ecologicalutility. A number of songbirds eat the
berriesin the winter. Downy woodpeckers also eatthe berries and
deer can eat the poison ivyplants and not be affected by the
toxins. Birdsthat feed on the plant’s fruit disperse theseeds in
their droppings. Since I like listeningto the songbirds, enjoy
watching woodpeckersand deer and like venison, I guess the fact
thatthese animals may find poison ivy enjoyableto eat gives the
plant someredemp tion—but notmuch. In the fall the redhues of their
colorful leavesadd contrasting colors to falllandscapes. And for
those ofus who enjoy the outdoors, weneed to appreciate poison
ivy,poisonous snakes, hornets, bitinginsects, skunks and bears.
There are vast numbers of people who neverventure into the woods.
The biting,stinging and irri tat ing flora and faunacollectively
act to keep city folks andtheir unattended children out of
ourwoodlands and in shop ping malls,bowling alleys and at home with
their video games.
Regular contributor David S. Lee is director ofthe Tortoise
Reserve, an international turtleconservation organization.
july • august 2014 winc 9
VIL
SE
SK
OG
EN
/FL
ICK
R
8 july • august 2014 winc
So to make sure my advice was on the righttrack I brought my
questions to my localphar macy, Anderson Drug Store in Elizabeth
-town. Since this is a small pharmacy, not a big-box drug store,
pharmacist Gene Andersonactu ally took the time to talk to me. He
in -formed me that Burrow’s solution helps todry weep ing sores.
Oatmeal baths (Aveeno)and cala mine lotion help to reduce itching
ifthe lesions are dry. Avoid dressings as exposedskin will heal
faster. If more than 25 percentof the body is involved then
prescribed oralsteroids may be in order.
Remember there is no known cure. Insevere cases physicians may
administersome cortisone derivative under carefullycontrolled
conditions. For people especiallyprone to poison ivy, prevention by
pre-expo -sure oral medications taken several monthsprior to
contact are available, but the resultsare controversial and may
have little effect.Severe exposure to the plant is serious,
andsecondary infections and other complica tions
are likely. On occasion exposure can havelethal results.
Many people who frequent the outdoorsand find themselves exposed
to poison ivywill rub the exposed area of their skin withthe
crushed leaves of jewel weed. Jewel weedcan often be found in areas
where poison ivygrows, so this is a quick and handy solution.OK, so
now you need to learn what two plantslook like, and since you
obviously did not do agood job on learning Rhus radicans, you prob
-ably are not yet on a fast track to becoming abotanist. Jewel weed
seems to work if donewithin minutes after exposure, but this prob a
-bly varies somewhat based on an individual’ssensitivity to the
toxin in poison ivy.
Not everyone who comes in contact withpoison ivy reacts to it,
and only about halfthe population is sensitive to mild contactwith
the plant. Somewhere between 15 and30 percent of the population is
immune, orthink they are. Recall the stereotype of themale student
in movies; loud, brash know-
wardrobe, her prominence grew in both thecomic books and films
as the feminism move -ment even created a demand for
botanicalfemale super villains. So let’s never under esti -mate the
powers of poison ivy.
What can I do if I get it? There actually is no cure, so
prevention is stillyour best bet. Learn what the plant looks
like,and wear sensible clothes when hiking andcamping in the woods.
To help learn the plantthere are a couple of simple but helpful say
-ings: “Leaves of three, let it be.” “Berrieswhite, take
flight.”
Oh, no, I got it. Washing with soap willserve to remove the
excess urushiol that couldbe translocated to other parts of the
body orto other persons. For those who find you for -got to put the
bar of yellow soap and bucketof warm water in your backpack there
are anynumber of after-the-fact topical lotions andcreams which
soothe the itching and to somedegree dry and control the extent of
blistering.
Although often thought of growing as avine, in some spaces
poison ivy will growas a shrub up to 3 feet tall.